Zillow's stock more than tripled after its IPO Wednesday, then fell back to settle up a mere 79% at the close. Initial public offerings have become a way to make huge profits in the market, if investors have the stomach for extreme risk -- and the access to buy in.

Russian search engine Yandex saw its IPO soar more than 55% on its first day of trading Tuesday. But while this Russian beauty managed to lure in investors with its ability to crush Google in the former USSR, some analysts are cautioning investors to temper their enthusiasm.

LinkedIn made its initial public offering Thursday, and soared immediately to more than twice its target price as Wall Street swooned over the stock. But IPOs are happening fairly regularly again after a recessionary lull: Why is there so much fuss over one not-so-major social networking site?

Though it's currently trading at $618, some investment pros view the stock as intrinsically inexpensive based on more than a couple of metrics. One measure in particular looks at Google's price-to-revenues ratio and sees plenty of room for the stock to rise.

New reports say Groupon could go public by the end of 2011, around the same time a Facebook IPO is expected. But even if they both priced their IPOs on the same day, it seems there will be no shortage of funding because IPO-starved investors are raring to go.

The Chinese online-video site had the strongest first-day rally of any company on a U.S. exchange since China's Baidu in 2005. But the flip side to promise is risk -- and the risks of pinning big hopes on Youku are also big.

Have the markets entered an IPO time warp? This week, Chinese deals were red-hot. Take a look at Youku.com. In Wednesday's debut, itsstock soared 161% to $33.44, raising $203 million. It marked the best return since Baidu hit the markets five years ago.

Google earned $7.64 a share in the third quarter excluding one-time items, handily beating expectations of $6.67. The strong results were an "October Surprise" of sorts for investors who have wondered whether Google's prodigious profit-making ability was beginning to wane.

Barry Diller's sprawling Internet company operates more than 50 diversified businesses in 30 countries, including such high-traffic sites as Ask.com, Match.com, CitySearch and Dictionary.com. It has gobs of cash and little debt. Yet its stock is stuck.

At least one analyst sees the stock price for Baidu, China's largest search engine, hitting $1,000 based on its stellar first-quarter earnings and net income growth of 165%. Part of that growth came at the expense of Google, which withdrew from mainland China in protest of that country's censorship policies.